Tapeworms are rebellious regardless of where they are found. Usually, they reside in the human stomach. Yes, your gut is a parasite’s natural habitat. They reside in the intestines, feed off of us, and lay eggs which we help to pass out and that way infect other animals.
Tapeworms perform quietly and relatively cautiously without putting our bodies in imminent danger. They understand that we are the host and won’t kill us and render them homeless. It is therefore hard to tell an infected person by symptoms. Often one will suspect their presence when you find traces in your poop. In rare cases of intestinal infection, there are signs like; upset stomach, loss of appetite, and weight loss. This is assuming that tapeworms are in your stomach. What if they shifted place of residence?
In the England Journal of Medicine, there was a contradicting case showing that tapeworms do not always reside in the gut. They can get to other parts of the body and cause severe damage. An Indian teenager infected by tapeworms is reported to have died of numerous cysts which had been formed by the parasites in his brain. His symptoms were characterized by tonic-clonic seizures, swollen eyes, confusion, and groin pain. Doctors found tapeworms in his brain and all over his body.
According to the Mayo Clinic, it is possible for the parasites to migrate from the intestines but this kind of infection that spreads to the entire body may be a result of different disease pathways common in pigs.
The type of tapeworm an animal gets depends on the stage of life of that worm when ingested. There is a species known as Taenia solium which begins its cycle as an egg in the human body and quickly leaves when we poop. When pigs feed on the feces or drink dirty water they ingest the worms. The eggs hatch in the pig’s intestines and migrate to the animals’ muscles and organs. There are also beef tapeworms but they do not cause cysts. Pig tapeworms easily cause cysts and the infection is referred to as cysticercosis which differs from what we term as ‘having tapeworms’.
This case study demonstrates that humans can develop cysts by ingesting tapeworm eggs. This teenage boy must have eaten the eggs and they hatched, migrated, and developed cysts.
The specific disease the boy suffered from is rare in developed countries because the hygiene measures limiting human and animal interaction are high. Unfortunately, that doesn’t reduce worldwide statistics. WHO estimates that between 2.5 and 8.3 million people suffer from neurocysticercosis annually. Most affected areas are developing parts of Asia, Africa, and Latin America. Subsistence farmers in these areas lack access to disease-preventing resources and infections become common. Those in developed countries like the USA must count themselves lucky and be careful when they travel internationally.
Coil, William H. “Studies on the Embryogenesis of the TapewormCittotaenia Variabilis (Stiles, 1895) Using Transmission and Scanning Electron Microscopy.” Parasitology Research, vol. 59, no. 2, 1979, pp. 151–159.
Mackiewicz, John S. “Caryophyllidea (Cestoidea): Evolution and Classification.” Advances in Parasitology, vol. 19, 1982, pp. 139–206.